These fanfictions usually involve Naruto having to learn to control the foxfire. This can lead to many interesting plotlines. For example, he may have to face off against enemies who are either afraid of or intrigued by his new power. Also, his relationships with his friends and mentors might change as they react to this new development in his abilities. There could be training arcs dedicated solely to mastering the foxfire, and sometimes the foxfire might have unique properties like being able to burn through certain types of jutsu defenses or having a special effect on the tailed beasts.
Typically, in 'naruto has foxfire' fanfiction, Naruto's power gets an extra dimension. The foxfire is often related to his connection with the Nine - Tails. It might be a new form of his chakra, or a special ability he discovers.
Another characteristic is that the foxfire often symbolizes Naruto's growth and evolution. It can be seen as a manifestation of his inner strength and his bond with the Nine - Tails. In some fanfictions, the foxfire may change color or intensity depending on Naruto's emotions, adding an extra layer of depth to his character. It also provides an opportunity for the author to create new and exciting battle scenes, as Naruto uses the foxfire in creative ways against his foes.
One great 'naruto has foxfire' fanfiction is 'Naruto's Foxfire Adventure' on FanFiction.net. It has an interesting plot where Naruto discovers a new form of his chakra that resembles foxfire and he uses it to overcome powerful enemies.
They usually introduce new animal species or expand on the existing ones in the Naruto world. Like there could be some rare, powerful animals that only Naruto can befriend. These animals might have unique abilities such as the power to heal or to create illusions on a large scale.
Typically, in 'Naruto has augments' fanfiction, Naruto gets some sort of extra abilities or enhancements. This could be physical like super strength or speed, or it could be related to his jutsu, making them more powerful. For example, he might gain the ability to control an element more efficiently or in a new way.
Often, they emphasize the loyalty between Naruto and his ninken. For example, in many such fanfictions, the ninken will stand by Naruto no matter how difficult the situation is.
Typically, in such fanfiction, Naruto is likely to be at the center of the story. The 'puppet' aspect might involve characters related to the puppet - using techniques in Naruto, like Kankuro perhaps. The 'harem' part means there will be multiple characters, usually female, having some sort of relationship with Naruto. It could be romantic, or they might be allies in a unique way.
The mystery around foxfire itself makes these stories spooky. Foxfire is a natural phenomenon that glows in the dark, but when it's associated with ghosts, it takes on a whole new level of eeriness. People don't really understand what causes it, so it's easy to attach supernatural beliefs to it.
Naruto breeds in fanfiction often show some of his personality traits too. They may be as friendly and outgoing as he is, making a lot of friends easily. And in terms of appearance, they might have his blond hair and blue eyes. Also, they could inherit his love for ramen and that could be a cute little detail in the fanfiction. Moreover, they may have a natural inclination towards protecting the village just like Naruto does.
In these fanfictions, Naruto often has enhanced combat abilities. The Crystal Release gives him a new way to attack and defend, like creating crystal structures for protection or sharp crystal shards as weapons.
In a particular foxfire ghost story, a group of hikers saw a foxfire in the middle of a forest trail. As they got closer, they heard strange whispers. The foxfire then disappeared and reappeared a short distance away. They later learned that the area was once a battleground, and the ghosts of the soldiers were said to be associated with the foxfire, perhaps trying to tell their story.
He is likely to be more mature. As the Hokage, he has to make tough decisions. He can't be as impulsive as he was when he was younger. His leadership skills are on full display, and he has a great sense of responsibility towards the village and its people.